This invention relates to an improved rope ladder and to a novel step therefor, as well as to assembly of the ladder.
Rope ladders, which are especially useful as pilot's ladders by which a local pilot boards or leaves a ship, have heretofore been made with wooden or metal steps. The present invention incorporates a molded elastomer step of hard rubber-like material.
In a copending application Ser. No. 933,645, filed Aug. 14, 1978 and now U.S. Pat. No. 4,177,878, I disclosed a rope ladder of the type in which there are two ropes on each side of each step and in which a novel wedging device is used to make the attachment secure. In the present invention, I am able to incorporate into the molded step, part of a similar but significantly different wedging system, thereby giving even surer and more reliant structure, since part of it is integral with the step itself. This new wedging system more tightly holds the ropes even when they are elongated.
The breakage and non-uniformity of wooden steps has long been a problem, and the use of molded elastomer greatly reduces breakage and gives improved quality control. Also, the elastomer has more resilience and so better receives strong impacts. It will not flex or bend under average work load, but on the other hand can yield to very strong loads or impacts without actually breaking.
Furthermore, the rope ladder of the present invention is simpler to make and to assemble than were previous wooden-step ladders, and the invention lends itself to a novel form of assembly that also places elongating force on the rope and secures the rope more securely as a result.